Those harboring a polymorphism of the dopamine active transporter 1 gene (DAT1), a gene involved in the reuptake of dopamine in chemical synapses, are 2.5 times more likely to develop dyskinesias when treated with L-Dopa while a different point mutation of DAT1 was shown to increase the risk of hallucination when treated with dopaminergic drugs [34,37]. Here, SLC6A3 is linked to drug-induced dyskinesia.